1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/altHashing.hpp"
  27 #include "classfile/javaClasses.inline.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/oop.inline.hpp"
  30 #include "oops/verifyOopClosure.hpp"
  31 #include "runtime/handles.inline.hpp"
  32 #include "runtime/thread.inline.hpp"
  33 #include "utilities/copy.hpp"
  34 #if INCLUDE_ALL_GCS
  35 #include "gc/g1/g1Allocator.inline.hpp"
  36 #endif
  37 
  38 bool always_do_update_barrier = false;
  39 
  40 BarrierSet* oopDesc::_bs = NULL;
  41 
  42 void oopDesc::print_on(outputStream* st) const {
  43   if (this == NULL) {
  44     st->print_cr("NULL");
  45   } else {
  46     klass()->oop_print_on(oop(this), st);
  47   }
  48 }
  49 
  50 void oopDesc::print_address_on(outputStream* st) const {
  51   st->print("{" INTPTR_FORMAT "}", p2i(this));
  52 
  53 }
  54 
  55 void oopDesc::print()         { print_on(tty);         }
  56 
  57 void oopDesc::print_address() { print_address_on(tty); }
  58 
  59 char* oopDesc::print_string() {
  60   stringStream st;
  61   print_on(&st);
  62   return st.as_string();
  63 }
  64 
  65 void oopDesc::print_value() {
  66   print_value_on(tty);
  67 }
  68 
  69 char* oopDesc::print_value_string() {
  70   char buf[100];
  71   stringStream st(buf, sizeof(buf));
  72   print_value_on(&st);
  73   return st.as_string();
  74 }
  75 
  76 void oopDesc::print_value_on(outputStream* st) const {
  77   oop obj = oop(this);
  78   if (this == NULL) {
  79     st->print("NULL");
  80   } else if (java_lang_String::is_instance(obj)) {
  81     java_lang_String::print(obj, st);
  82     print_address_on(st);
  83   } else {
  84     klass()->oop_print_value_on(obj, st);
  85   }
  86 }
  87 
  88 
  89 void oopDesc::verify_on(outputStream* st) {
  90   if (this != NULL) {
  91     klass()->oop_verify_on(this, st);
  92   }
  93 }
  94 
  95 
  96 void oopDesc::verify() {
  97   verify_on(tty);
  98 }
  99 
 100 intptr_t oopDesc::slow_identity_hash() {
 101   // slow case; we have to acquire the micro lock in order to locate the header
 102   Thread* THREAD = Thread::current();
 103   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
 104   HandleMark hm(THREAD);
 105   Handle object(THREAD, this);
 106   return ObjectSynchronizer::identity_hash_value_for(object);
 107 }
 108 
 109 // When String table needs to rehash
 110 unsigned int oopDesc::new_hash(juint seed) {
 111   EXCEPTION_MARK;
 112   ResourceMark rm;
 113   int length;
 114   jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
 115   if (chars != NULL) {
 116     // Use alternate hashing algorithm on the string
 117     return AltHashing::murmur3_32(seed, chars, length);
 118   } else {
 119     vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
 120     return 0;
 121   }
 122 }
 123 
 124 VerifyOopClosure VerifyOopClosure::verify_oop;
 125 
 126 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
 127   oop obj = oopDesc::load_decode_heap_oop(p);
 128   guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
 129 }
 130 
 131 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
 132 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
 133 
 134 // type test operations that doesn't require inclusion of oop.inline.hpp.
 135 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
 136 bool oopDesc::is_array_noinline()             const { return is_array();               }
 137 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
 138 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
 139 
 140 bool oopDesc::has_klass_gap() {
 141   // Only has a klass gap when compressed class pointers are used.
 142   return UseCompressedClassPointers;
 143 }
 144 
 145 #if INCLUDE_CDS_JAVA_HEAP
 146 bool oopDesc::is_archive_object(oop p) {
 147   return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
 148 }
 149 #endif